1. Field of the Invention
This invention relates to an electronic typewriter having a function of checking the spelling of a word input by an key operation, and more particularly to an electronic typewriter having a function of checking the spelling of a word in response to a space key, a carriage return (CR) key operation or the like.
2. Description of the Related Art
In general, a spelling checking unit having a dictionary memory which stores the correct spellings of words to be input by key operations is provided in an electronic typewriter with a spelling-checking function. When a space key is operated after a character key or keys on a keyboard are operated to enter a word, the spelling of the word input immediately before the operation of the space key is checked. In this case, if an error is detected in the spelling, an alarm such as buzzer sound is generated, for example. When the typist hears the alarm sound, the typist determines the misspelled word which has been input and printed by the key operation, moves back the carriage to the position of the misspelled word, and then corrects the misspelled word.
Further, in an ordinary electronic typewriter, when the carriage has reached a position at or near the right margin provided at the end portion of each line, a carriage return key is operated to move the carriage back to a home position and change lines. In this case, the carriage return key (CR) is operated without operating the space key after the operation of inputting a final word, and at this time the spelling of the word input immediately before the operation of the carriage return key is checked in response to the operation of the carriage return key. That is, when the carriage return key is operated, the spelling of the word input immediately before the operation of the carriage return key is checked and then the carriage return operation is effected.
However, the electronic typewriter with the spelling-checking function has the following problems. As described before, when the carriage return key is operated, the spelling of the word input immediately before the operation of the carriage return key is checked and then the carriage return operation is automatically effected. If the misspelling is detected in the key-in word, a buzzer sound is generated. Although the buzzer sound is generated only for a short period of time, the carriage is set on the printing starting position or the left end of the next line when the typist has heard the buzzer sound.
Therefore, in a case where the misspelling is detected and the misspelled word is corrected, it is necessary to set back the carriage return on the former line by operating a reverse index key or the like, and then move it back to the position of the word printed near the right margin by operating a space key, back space key or the like.
Thus, the word correction operation becomes extremely complicated, lowering the operability of the electronic typewriter in its entirety.
Further, the operations of checking the spellings started in response to the operations of the carriage return key and the space key are effected under the same operating condition. That is, only if the carriage return key or space key is operated when the carriage is positioned on the right side of the printed word, the spelling of the word is checked.
When, for example, a last word on a line is misspelled, the carriage is first set on a wrong letter or character of the misspelled word, and the misspelled word is corrected. At this time, in order to check the spelling of the corrected word, it is necessary to set the carriage next to the right side of the corrected word by operating the space key or the like and then operate the carriage return key.
Further, there is a possibility that a word other than the last word on a line is corrected after which additional words of the line are input, and then the carriage return key is operated to change lines. In this case, the spelling of the corrected word is not checked. That is, the spellings of all the input words cannot always be checked.